Well... maybe not the world (...yet), but definitely taking over and controlling their human owners. Found this study to be amusing:
http://news.yahoo.com/s/livescience/20090713/sc_livescience/catsdocontrolhumansstudyfinds
http://news.bbc.co.uk/2/hi/science/nature/8147566.stm
http://news.yahoo.com/s/livescience/20090713/sc_livescience/catsdocontrolhumansstudyfinds
http://news.bbc.co.uk/2/hi/science/nature/8147566.stm